Centerboard removal

Submitted by sam secrest on Mon, 02/09/2009 - 16:22

I know that I have removed the centerboard on a Thistle while the boat was in the water, but the Scot is rigged a bit differently with the cable around a block and the stainless bolt thru it and the board. Does anyone have a formula for this? I know if we put the boat on its side, we could slide it out, but that means taking it off the trailor, etc.

Comments

Put the boat in the water, deep enough to put down the board. Tie off to a dock, if possible.
Put the centerboard down. Then disconnect the shackle on the end of the centerboard cable that is attached to the keelson in the stanchion.
Put a sturdy (1/4") loop of line through the pulley on the head of the centerboard.
DO NOT remove the bolt holding the rollers and pulley. Doing so will cause the board to fall out of the bottom of the boat. Not fun.
Pad the seats, floor and deck, so if the board bumps anything, it doesn't scuff or ding things. Think about your path from CB slot to dock. The board is heavy and awkward. It weights about 105 lbs.
Put a 2x4 or similar sturdy handle, about 4 feet long, through the loop that you attached to the pulley. I have found it easiest with three people. Two lift the ends of the handle, and the third guide the free (heavy) bottom end to the place you want it to go.
It seems to work best if the two lifters stand on the seats, to get the board higher, and the third, who is controlling, stands aft of the board as it comes up out of the slot.
I carried mine home in the car, but I have also seen folks pad the board, and take it home in the boat. Be careful it doesn't slide around in the boat. It is heavy and can damage the boat or itself. It rode fine in the minivan.
I cheated and put mine pack in with the boat on it's side, when I replaced the gasket. It seems like it would be easier to put it back in with the boat in the water.
Have fun,
Phil Scheetz
FS 4086

I think Phil Sheetz is right. One minor variation is to use the main halyard. Attach its shackle to the loop you put through the pulley. As you crank on the halyard the centerboard will rise. You may need to slide it fore and aft a bit to get it free of the centerboard trunk. Once the tip is clear you can CAREFULLY ease the winch and lower the board to the cockpit sole.
If you are careful, you might choose, instead, to crank the winch more so that the tip will clear the seats. Once the tip is on the dock, ease little by little and you don't have to struggle to get the board out of the boat. I find I can do this single handed.
Phil's cautions about weight and having the boat secured are important.
Frank Kieliszek
FS 1803

While we're on the subject, I hope someone can shed light on replacing the centerboard rollers and bolt. I slammed a submerged stump last year and bent the bolt into a shallow V. Does the board have to be removed? Is replacement of the bolt and rollers something that can be done on the trailer?
Kurt

I have a question to and about Frank Kieliszek's method of using the main halyard to remove the board.
It seems to me that lifting a board that heavy with the halyard is not safe, seems like way too much weight on all the hardware. How much can the mainsail weigh? I would think the handle would sheer right off.
Peter Dube'
5815
Vero Beach

I have removed the centerboard a couple of times and would recomend two methods;
First is to launch the boat on the grass, put the rig up and use it to lay the boat on its side. This is not difficult to do and there are other posts on this forum with details. Once the boat is on its side you remove the roller bolt and slide the board out of the trunk. This is easy and safe.
The second method would be to use the hoist at your club (if you have one) Launch the boat tie it off under the hoist and use the hoist to raise the board out and place it safely on the gound or dock.
Theoretically, using the main halyard should work but the chances of trouble are much higher than the two methods above. The halyard wire should have a breaking strength around 400 to 500 lbs. Hopefully the nicro press sleeve would hold and the crank used would be stainless or a ratchet drive, using the aluminum crank would be inviting trouble.
Should anything fail while the board is being lifted the likely result will be breaking the "ears" (where the roller bolt passes through the centerboard) off and the board is ruined. A new centerboard is over $1,000.
To change the rollers or bolt while on the trailer is easy. Using the centerboard line slowly lower the board so that it will come to rest on some blocks or the tailer axel which has a cushion in place to protect the edge of the board. A throwable cushion works well. Once the weight of the board is on the cushion the load on the roller bolt is removed and it can be removed.

I'm glad to see that people are thinking about safety. I am no marine engineer. Here's my thoughts: If the Harken web site is to be believed, 1/16" stainless wire rope has a breaking strength of about 500 lbs. Wire rope weakens with age and use. I bet I am still working with a safety margin much greater than 2:1. When I consider that a cunningham has 6:1 purchase, I am not surprised that tension on the main halyard may often exceed the 110# weight of the centerboard.
Clearly, if something breaks while lifting or hoisting the centerboard, you are in trouble. A heavy object falling long distances into a fiberglass boat is no fun.
I thought the question was whether there was an easy way to remove the board in the water. I live within 75 feet of my dock. I am surrounded by woods. When I need to remove my board it makes more sense for me to do this carefully at dockside, than to haul the boat, trailer it to a park, get the boat off the trailer, re-rig the mast, turn the boat on its side, and then remove the board.
No doubt: removing the board on dry land has got to be safer. I think it is reasonably safe when done carefully at dockside.
By the way, great forces are not required. This process does not break the aluminum crank. If you are putting that much force on the board to raise it, something is wrong. The greatest fear I have is loosing control when I ease the board. If I let the crank slip out of the winch, I will loose control of the board while it is up in the air.
I hope this approach helps those who need to remove the board in the water without the aide of assistants or a hoist.
Frank Kieliszek

Frank,
Thank you for replying to my safety concerns of using the main halyard and winch to remove the board. I had thought that the hardware would not be sufficient to lift such a load, I stand corrected. But now that I think about it, there have been numerous posts of skippers BREAKING the halyard by raising the main too high, so I guess the winch is up to the task. And as previously mentioned in this thread, the halyard itself has a capacity of 4 or 5 hundred pounds.
I am amazed still, that the aluminum handle takes that load. It would be quite a mess if she sheered with the board lifted over the boat ... I think I would use the stainless crank.
Peter Dube'
5815 Vero Beach, FL

Someone at our club put a hole in the bottom of his Scot by dropping his board on the floor of the boat.
I think that a crane might be overkill but the safest. The only point of failure would be the rope that you tie to the centerboard pulley.
If you are using the mast winches use stainless. I have busted aluminum cranks with very little pressure on them because they may have been cracked from fatigue. Aluminum is funny that way. Check the condition of you halyards and pulleys. They do fray and wear out after a while. Another important thing is to have a second person help. I have done it myself but if something goes wrong you will be in trouble with a 100 pound board swinging around.
Here is a picture of how someone at our club tied a rope onto the CB pulley. The previous post about tripling it up is probably a good idea for safety. The guy on the left guided the board out and onto the floor of the boat. The guy on the right operated the winch. I had a vid but that is broken for some reason I will try to get it back. http://tinyurl.com/bzog9e

If a hoist is not available, it is best to put the boat in shallow, calm water and lower the board onto the lake bottom so that the cable goes slack and the shackle can be opened to free the cable. Slide the cable back through the ears of the board. Have someone play out the boat's bow tie-up line so that the boat can move back while you pull back on the head of the board. The board will stand up in the trunk as the boat slides back. You now only need to lift the board about 18" to get the bottom of the board clear of the top of the trunk. If it slips, it will not fall far enough to damage anything. Two people in the boat make it much easier and have a cushion handy to rest the board on after it is clear of the trunk. I like to do this in the morning when the water is usually calm so that the board does not grind against the bottom too much.
Harry Carpenter

quote:[i]Originally posted by HarryC[/i]
[br]If a hoist is not available, it is best to put the boat in shallow, calm water and lower the board onto the lake bottom so that the cable goes slack and the shackle can be opened to free the cable. Slide the cable back through the ears of the board. Have someone play out the boat's bow tie-up line so that the boat can move back while you pull back on the head of the board. The board will stand up in the trunk as the boat slides back. You now only need to lift the board about 18" to get the bottom of the board clear of the top of the trunk. If it slips, it will not fall far enough to damage anything. Two people in the boat make it much easier and have a cushion handy to rest the board on after it is clear of the trunk. I like to do this in the morning when the water is usually calm so that the board does not grind against the bottom too much.
Harry Carpenter

As usual the best advice is to call the builder first! That is a great idea. I am always worried about dropping it. In my last post I sad that I had a vid. Here it is... http://tinyurl.com/dfwj7c

You can win races on our little lake if you cut across the point, but there is a risk. Our man made lake used to be a valley full of trees. When they filled the valley with water, they forgot to remove the stumps. One in three times that you cut across on your way to victory, your centerboard hits a stump. So, you gotta patch up your centerboard every now and then. I have pulled mine three times. In the past I have had three big guys from our cliub handy to help me. I prefer the in the water method. I used the main halyard "crane" method. Keep in mind that the "axle" of the sheave is a small aluminum bolt shaft. A standard socket wrench with extension fits perfectly into the female opening of the winch. No way use the aluminum crank. You don't have the leverage you need. Do wiggle the centerboard as you put tension on the halyard. Otherwise, it will tend to jamb slightly and greatly increase the tension. I recommend hooking up the jib halyard with 6' of 1/4" line as a backup safety line. If the main halyard lets go for any reason, the fall will damage the boat, badly. The 1/4" all nylon will act as a stretchy brake. If you are strong you can handle the CB, but be forwarned: There is a 90 lb lead plate in the lower 18" of the board. The center of balance is about 22" from the lower tip. I like to put some 1x12 pine in the bottom of the boat, just in case.

With the boat on the side, the board obviously will be pulled downwards. You can rotate the board by hand and a little lifting. When I clean my bottom with the boat on its side and the mast is safely secured so it doesn't flip back up, I release the centerboard takeup line and slowly pull the board out. You will have to work it from inside to get it started and then go around the other side and pull it out more. It may take a few trips back and forth to get it all the way down. If you are going to remove it, disconnect the line at the centerboard roller and remove the board via the cockpit. If you are going to take it out from the bottom, you will need to remove the rollers. Having someo ne help you will make it a lot easier.